Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab60156bf7219720…

MALICIOUS

PDF

81.6 KB Created: 2021-09-19 04:34:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 42c6f1ea70f023162227ee967f4ab8b3 SHA-1: b5cc35da1f142b086e6cbdc1b2d3860562adf13c SHA-256: ab60156bf7219720627fa86e1aef53d475d2eef8778f75653149ef8ec142036e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs that point to various domains, many of which are associated with link farms or compromised upload storage. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link distribution, suggesting a phishing or malware distribution campaign. No scripts were extracted, but the primary attack vector appears to be directing users to external, potentially malicious, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://archism.ru/uplcv?utm_term=0.8+radians+to+degrees
    • http://shinies.ru/img/lib/file/65209242417.pdf
    • http://teresachild.com/upload/files/73540617333.pdf
    • http://daiduongmetal.com/uploads/ckfinder/files/forifugipedilaziduga.pdf
    • http://airmon.hu/images/files/sivoliwekajivesuruka.pdf
    • http://sinorarechem.com/upload/files/wuladarir.pdf
    • http://styrexon.cz/userfiles/file/pakaso.pdf
    • http://mariondhuique-mayer.com/data/file/82070089519.pdf
    • https://sanruouvang.net/images/uploaded/file/72528201391.pdf
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/55028813792.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/161338a161691b---25040502303.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161434ccbebe91---xobalowija.pdf
    • https://musikkursus.dk/userfiles/file/73933875026.pdf
    • http://bbfederico2.net/userfiles/file/duxutibikugot.pdf
    • https://camping-du-lac-dijon.com/userfiles/fichiers/nesalubatawumexedegubi.pdf
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/vetumunowup.pdf
    • http://xfswchem.com/upload/files/70445148746.pdf
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/wewonom.pdf
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/c869bfd2282f58b6b00a9ea5230aad91/66963405933.pdf
    • https://amadesafar.ir/basefile/amadesafarir/files/53959680277.pdf
    • http://frigotechreina.com/userfiles/files/nuwav.pdf
    • http://bjyhyy.cn/filespath/files/20210907151505.pdf
    • http://agrostroi-proekt.ru/ckfinder/userfiles/files/89314086023.pdf
    • https://yaslibakicisi.net/userfiles/file/bameninelubuxezifavojo.pdf
    • http://tokyosushilohaus.com/uploads/files/sibovivuk.pdf
    • http://vlajamo.cz/images/file/61171109344.pdf
    • https://bywuf.org/upload/editor/files/87337794326.pdf
    • http://artemon.nl/userfiles/file/pofegokafexigepewavekel.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd3d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3D 16792 bytes
font_01_sfnt_off0000f54f.bin
3d25820a4db88e1fcf0c0e5f20afe45ba314e4bfe9f186232d306d94381129d1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF54F 16568 bytes
font_02_sfnt_off00011fdb.bin
d7420827bb36048f40e2b2eadf458758b9def73f5941da80d45d913b57141652
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FDB 10676 bytes